This project has concerned the development of animal models of neurological disease produced by exposure to synthetic and naturally occurring neurotoxins in the environment. The interaction of various toxins and neurotransmitters and hormones in the CNS have provided the focus for combined behavioral and neurochemical studies emphasizing basic mechanisms of action of proposed neurotoxins. Major topics studied this past year were: (1) effects of heavy metals on neurotransmitter and neuroendocrine function; (2) effects of estrogens on basal ganglia function; (3) effects of artificial food colors on neuronal membranes and neurotransmission; (4) genetically determined variations in neurotoxicity.